head strip with guard

   1: -module(play).

   2: -export([headstrip/1]).

   3:  

   4: headstrip([]) -> ok;

   5: headstrip([Head|Rest]) when Head > 4 ->

   6:     io:format("~w bingo!~n", [Head]),

   7:     headstrip(Rest);

   8: headstrip([Head|Rest]) -> 

   9:     io:format("~w~n",[Head]),

  10:     headstrip(Rest).

3> play:headstrip([1,2,3,4,5,6,7,8,9]).
1
2
2
3
4
5 bingo!
6 bingo!
7 bingo!
8 bingo!
9 bingo!
ok